Holding on to each other in their grief, the family of one of the four Welsh miners killed in the Gleision pit disaster laid cards and flowers at the spot where the men last saw the light of day.

Phillip Hill's daughter Kyla stood in tears at the entrance to Swansea valley mine to pay tribute to the 45-year-old who lost his life when the narrow tunnels flooded during blasting on Thursday morning, along with his workmates Garry Jenkins, 39, David Powell, 50, and Charles Breslin, 62.

The card she laid was as simple as it was touching. It read: "Hi dad, I love and miss you forever. Love you all the money in the world and America. From Kyla x"

Another card from Mr Hill's family said: "Thank you for being part of our lives. Our girls will be safe with me. Miss you always. Donna x Meg"

The family also left a third bunch of flowers and another card, which said: "Phil, Kyla and Meg are in good hands, so sleep tight.

They were sentiments that reflected the immense grief that has struck the mining communities of south Wales, where Peter Hain, the MP for Neath, said the tragedy had "stabbed through the heart of the community".

Among the other well-wishers leaving tributes to the four men were the widow and daughters of Alan Jones, a miner killed underground in 1976.

On a card they wrote: "To the families of miners lost.

"May you find courage and strength over the coming days, months and years ahead. Our sincere sympathy and our thoughts are with you.

Another tribute said: "The day's work is done, your tools are 'on the bar'. No more sweat and no more pain. Rest in peace."

Other well-wishers said: "To the families of the miners.

"No words can ease your pain. Just to know you are in our thoughts.

"Victoria, Amy, Alison (Rhos)."

Another card said simply: "Rest in peace boys. Wales is proud of you xxxx"

Mr Hain last night launched an appeal to held the families of the four men, now left without the support of their principal breadwinners.

On the minersappealfund.org website, Mr Hain wrote: "The deaths of four miners at the Gleision Colliery was the worst mining accident Wales has seen for generations.

"This tragedy is a stab through the heart of the community. We can't even imagine what the families are going through.

"But they need our help to survive and recover in the future. So today I am launching an appeal fund to help support them and will be announcing other patrons shortly.

"Please give what you can to support the families."

The alarm was raised early on Thursday after the shaft at Gleision was flooded, trapping the men. It had been hoped that the miners – originally part of a group of seven – might have found refuge in an air pocket following the accident.

But those hopes were gradually dashed on Friday, despite frantic efforts to rescue the men, with the police announcing at 6pm that the body of the last of the four had been found.

In a joint statement, the Wales Office and the Health and Safety Executive said an investigation has been launched.

"Following the tragic incident at Gleision Colliery on September 15, an investigation is now under way," the statement said. "HSE specialist mine inspectors are on site. They are working closely with South Wales Police, who are leading the investigation and have appointed a senior investigating officer.

"When an investigation into the incident begins, initially the police will have primacy in accordance with the Work-Related Deaths Protocol agreed between the police, HSE, local authorities and the Crown Prosecution Service and HSE will provide technical support.

"At a later point it may be deemed appropriate for primacy of the investigation to be passed to HSE, as has happened in other incidents."

Swansea City Football Club held a minute's silence for the miners who lost their lives in the tragedy before the team's Premier League game against West Bromwich Albion at the Liberty Stadium in Swansea.

The club's chairman, Huw Jenkins, described the disaster as a "dreadful tragedy which has affected the whole community", adding: "Our sympathy goes out to the families who have lost loved ones in extremely sad circumstances."

Messages of support have poured in from around the world, with well-wishers everywhere praying for some good news until the final death was announced.

David Cameron described the tragedy as a "desperately, desperately sad situation".

The Prime Minister said the anguish of the miners' families was "intense" but that it was clear the emergency services had done everything they could.

The family Mr Powell called for the pit to be shut down and sealed for ever. Mr Powell’s son Daniel, 26, escaped by running out of the shaft as it filled with thousands of gallons of water.

A family friend said yesterday: “All Daniel kept saying afterwards was that it isn’t safe down there. The family want to see the pit shut down for good – they don’t want anyone else to go through the nightmare they have suffered over the last few days.

“The pit was constantly filling with water – it was a constant battle to keep it pumped out so the men could go down there.”

Kelvin Davies, Mr Powell’s brother in law, said: “We’d like to thank the community - especially in Rhos - which has been wonderful. They were very very generous with the time and support they gave to the families. They have been fantastic. We’d also like to day thank you to the police and rescue crews, who did everything they could.

“My sister Lynette is absolutely devastated. Daniel is feeling it more than anyone else. He’s really devastated. It was an awful experience.”